Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 2 | * Copyright (C) 2000 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3 | * Licensed under the GPL |
| 4 | * |
| 5 | * Ported the filesystem routines to 2.5. |
| 6 | * 2003-02-10 Petr Baudis <pasky@ucw.cz> |
| 7 | */ |
| 8 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 9 | #include <linux/fs.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 10 | #include <linux/module.h> |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 11 | #include <linux/mm.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 12 | #include <linux/pagemap.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 13 | #include <linux/statfs.h> |
Tejun Heo | 5a0e3ad | 2010-03-24 17:04:11 +0900 | [diff] [blame] | 14 | #include <linux/slab.h> |
Miklos Szeredi | dd2cc4d | 2008-02-08 04:21:43 -0800 | [diff] [blame] | 15 | #include <linux/seq_file.h> |
Jiri Kosina | 6966a97 | 2008-02-09 00:10:14 -0800 | [diff] [blame] | 16 | #include <linux/mount.h> |
Al Viro | d0352d3 | 2010-06-06 21:51:16 -0400 | [diff] [blame] | 17 | #include <linux/namei.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 18 | #include "hostfs.h" |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 19 | #include "init.h" |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 20 | #include "kern.h" |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 21 | |
| 22 | struct hostfs_inode_info { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 23 | int fd; |
Al Viro | aeb5d72 | 2008-09-02 15:28:45 -0400 | [diff] [blame] | 24 | fmode_t mode; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 25 | struct inode vfs_inode; |
| 26 | }; |
| 27 | |
| 28 | static inline struct hostfs_inode_info *HOSTFS_I(struct inode *inode) |
| 29 | { |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 30 | return list_entry(inode, struct hostfs_inode_info, vfs_inode); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 31 | } |
| 32 | |
Josef Sipek | 680b0da | 2006-12-08 02:37:05 -0800 | [diff] [blame] | 33 | #define FILE_HOSTFS_I(file) HOSTFS_I((file)->f_path.dentry->d_inode) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 34 | |
Nick Piggin | fe15ce4 | 2011-01-07 17:49:23 +1100 | [diff] [blame] | 35 | static int hostfs_d_delete(const struct dentry *dentry) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 36 | { |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 37 | return 1; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 38 | } |
| 39 | |
Al Viro | e16404e | 2009-02-20 05:55:13 +0000 | [diff] [blame] | 40 | static const struct dentry_operations hostfs_dentry_ops = { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 41 | .d_delete = hostfs_d_delete, |
| 42 | }; |
| 43 | |
| 44 | /* Changed in hostfs_args before the kernel starts running */ |
Paolo 'Blaisorblade' Giarrusso | a6eb0be | 2007-03-07 20:41:08 -0800 | [diff] [blame] | 45 | static char *root_ino = ""; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 46 | static int append = 0; |
| 47 | |
| 48 | #define HOSTFS_SUPER_MAGIC 0x00c0ffee |
| 49 | |
Arjan van de Ven | 92e1d5b | 2007-02-12 00:55:39 -0800 | [diff] [blame] | 50 | static const struct inode_operations hostfs_iops; |
| 51 | static const struct inode_operations hostfs_dir_iops; |
Al Viro | d0352d3 | 2010-06-06 21:51:16 -0400 | [diff] [blame] | 52 | static const struct inode_operations hostfs_link_iops; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 53 | |
| 54 | #ifndef MODULE |
| 55 | static int __init hostfs_args(char *options, int *add) |
| 56 | { |
| 57 | char *ptr; |
| 58 | |
| 59 | ptr = strchr(options, ','); |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 60 | if (ptr != NULL) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 61 | *ptr++ = '\0'; |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 62 | if (*options != '\0') |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 63 | root_ino = options; |
| 64 | |
| 65 | options = ptr; |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 66 | while (options) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 67 | ptr = strchr(options, ','); |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 68 | if (ptr != NULL) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 69 | *ptr++ = '\0'; |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 70 | if (*options != '\0') { |
| 71 | if (!strcmp(options, "append")) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 72 | append = 1; |
| 73 | else printf("hostfs_args - unsupported option - %s\n", |
| 74 | options); |
| 75 | } |
| 76 | options = ptr; |
| 77 | } |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 78 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 79 | } |
| 80 | |
| 81 | __uml_setup("hostfs=", hostfs_args, |
| 82 | "hostfs=<root dir>,<flags>,...\n" |
| 83 | " This is used to set hostfs parameters. The root directory argument\n" |
| 84 | " is used to confine all hostfs mounts to within the specified directory\n" |
| 85 | " tree on the host. If this isn't specified, then a user inside UML can\n" |
| 86 | " mount anything on the host that's accessible to the user that's running\n" |
| 87 | " it.\n" |
| 88 | " The only flag currently supported is 'append', which specifies that all\n" |
| 89 | " files opened by hostfs will be opened in append mode.\n\n" |
| 90 | ); |
| 91 | #endif |
| 92 | |
Al Viro | e919305 | 2010-06-06 23:16:34 -0400 | [diff] [blame] | 93 | static char *__dentry_name(struct dentry *dentry, char *name) |
| 94 | { |
Nick Piggin | ec2447c | 2011-01-07 17:49:29 +1100 | [diff] [blame] | 95 | char *p = dentry_path_raw(dentry, name, PATH_MAX); |
Al Viro | e919305 | 2010-06-06 23:16:34 -0400 | [diff] [blame] | 96 | char *root; |
| 97 | size_t len; |
| 98 | |
Al Viro | e919305 | 2010-06-06 23:16:34 -0400 | [diff] [blame] | 99 | root = dentry->d_sb->s_fs_info; |
| 100 | len = strlen(root); |
| 101 | if (IS_ERR(p)) { |
| 102 | __putname(name); |
| 103 | return NULL; |
| 104 | } |
Al Viro | 850a496 | 2010-08-18 06:18:57 -0400 | [diff] [blame] | 105 | strlcpy(name, root, PATH_MAX); |
Al Viro | e919305 | 2010-06-06 23:16:34 -0400 | [diff] [blame] | 106 | if (len > p - name) { |
| 107 | __putname(name); |
| 108 | return NULL; |
| 109 | } |
| 110 | if (p > name + len) { |
| 111 | char *s = name + len; |
| 112 | while ((*s++ = *p++) != '\0') |
| 113 | ; |
| 114 | } |
| 115 | return name; |
| 116 | } |
| 117 | |
Al Viro | c532222 | 2010-06-06 20:42:10 -0400 | [diff] [blame] | 118 | static char *dentry_name(struct dentry *dentry) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 119 | { |
Al Viro | e919305 | 2010-06-06 23:16:34 -0400 | [diff] [blame] | 120 | char *name = __getname(); |
| 121 | if (!name) |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 122 | return NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 123 | |
Al Viro | e919305 | 2010-06-06 23:16:34 -0400 | [diff] [blame] | 124 | return __dentry_name(dentry, name); /* will unlock */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 125 | } |
| 126 | |
Al Viro | c532222 | 2010-06-06 20:42:10 -0400 | [diff] [blame] | 127 | static char *inode_name(struct inode *ino) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 128 | { |
| 129 | struct dentry *dentry; |
Nick Piggin | ec2447c | 2011-01-07 17:49:29 +1100 | [diff] [blame] | 130 | char *name; |
| 131 | |
| 132 | dentry = d_find_alias(ino); |
| 133 | if (!dentry) |
Al Viro | e919305 | 2010-06-06 23:16:34 -0400 | [diff] [blame] | 134 | return NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 135 | |
Nick Piggin | ec2447c | 2011-01-07 17:49:29 +1100 | [diff] [blame] | 136 | name = dentry_name(dentry); |
| 137 | |
| 138 | dput(dentry); |
| 139 | |
| 140 | return name; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 141 | } |
| 142 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 143 | static char *follow_link(char *link) |
| 144 | { |
| 145 | int len, n; |
| 146 | char *name, *resolved, *end; |
| 147 | |
| 148 | len = 64; |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 149 | while (1) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 150 | n = -ENOMEM; |
| 151 | name = kmalloc(len, GFP_KERNEL); |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 152 | if (name == NULL) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 153 | goto out; |
| 154 | |
WANG Cong | ea7e743 | 2008-11-19 15:36:46 -0800 | [diff] [blame] | 155 | n = hostfs_do_readlink(link, name, len); |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 156 | if (n < len) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 157 | break; |
| 158 | len *= 2; |
| 159 | kfree(name); |
| 160 | } |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 161 | if (n < 0) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 162 | goto out_free; |
| 163 | |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 164 | if (*name == '/') |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 165 | return name; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 166 | |
| 167 | end = strrchr(link, '/'); |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 168 | if (end == NULL) |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 169 | return name; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 170 | |
| 171 | *(end + 1) = '\0'; |
| 172 | len = strlen(link) + strlen(name) + 1; |
| 173 | |
| 174 | resolved = kmalloc(len, GFP_KERNEL); |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 175 | if (resolved == NULL) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 176 | n = -ENOMEM; |
| 177 | goto out_free; |
| 178 | } |
| 179 | |
| 180 | sprintf(resolved, "%s%s", link, name); |
| 181 | kfree(name); |
| 182 | kfree(link); |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 183 | return resolved; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 184 | |
| 185 | out_free: |
| 186 | kfree(name); |
| 187 | out: |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 188 | return ERR_PTR(n); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 189 | } |
| 190 | |
David Howells | 0a370e5 | 2008-02-07 00:15:50 -0800 | [diff] [blame] | 191 | static struct inode *hostfs_iget(struct super_block *sb) |
| 192 | { |
Al Viro | 52b209f | 2010-06-06 18:43:19 -0400 | [diff] [blame] | 193 | struct inode *inode = new_inode(sb); |
David Howells | 0a370e5 | 2008-02-07 00:15:50 -0800 | [diff] [blame] | 194 | if (!inode) |
| 195 | return ERR_PTR(-ENOMEM); |
David Howells | 0a370e5 | 2008-02-07 00:15:50 -0800 | [diff] [blame] | 196 | return inode; |
| 197 | } |
| 198 | |
David Howells | 726c334 | 2006-06-23 02:02:58 -0700 | [diff] [blame] | 199 | int hostfs_statfs(struct dentry *dentry, struct kstatfs *sf) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 200 | { |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 201 | /* |
| 202 | * do_statfs uses struct statfs64 internally, but the linux kernel |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 203 | * struct statfs still has 32-bit versions for most of these fields, |
| 204 | * so we convert them here |
| 205 | */ |
| 206 | int err; |
| 207 | long long f_blocks; |
| 208 | long long f_bfree; |
| 209 | long long f_bavail; |
| 210 | long long f_files; |
| 211 | long long f_ffree; |
| 212 | |
Al Viro | 601d2c3 | 2010-06-06 17:53:01 -0400 | [diff] [blame] | 213 | err = do_statfs(dentry->d_sb->s_fs_info, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 214 | &sf->f_bsize, &f_blocks, &f_bfree, &f_bavail, &f_files, |
| 215 | &f_ffree, &sf->f_fsid, sizeof(sf->f_fsid), |
Richard Weinberger | 1b627d5 | 2010-10-26 14:21:18 -0700 | [diff] [blame] | 216 | &sf->f_namelen); |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 217 | if (err) |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 218 | return err; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 219 | sf->f_blocks = f_blocks; |
| 220 | sf->f_bfree = f_bfree; |
| 221 | sf->f_bavail = f_bavail; |
| 222 | sf->f_files = f_files; |
| 223 | sf->f_ffree = f_ffree; |
| 224 | sf->f_type = HOSTFS_SUPER_MAGIC; |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 225 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 226 | } |
| 227 | |
| 228 | static struct inode *hostfs_alloc_inode(struct super_block *sb) |
| 229 | { |
| 230 | struct hostfs_inode_info *hi; |
| 231 | |
Al Viro | 601d2c3 | 2010-06-06 17:53:01 -0400 | [diff] [blame] | 232 | hi = kzalloc(sizeof(*hi), GFP_KERNEL); |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 233 | if (hi == NULL) |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 234 | return NULL; |
Al Viro | 601d2c3 | 2010-06-06 17:53:01 -0400 | [diff] [blame] | 235 | hi->fd = -1; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 236 | inode_init_once(&hi->vfs_inode); |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 237 | return &hi->vfs_inode; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 238 | } |
| 239 | |
Al Viro | e971a6d | 2010-06-06 15:16:17 -0400 | [diff] [blame] | 240 | static void hostfs_evict_inode(struct inode *inode) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 241 | { |
Mark Fasheh | fef2665 | 2005-09-09 13:01:31 -0700 | [diff] [blame] | 242 | truncate_inode_pages(&inode->i_data, 0); |
Al Viro | e971a6d | 2010-06-06 15:16:17 -0400 | [diff] [blame] | 243 | end_writeback(inode); |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 244 | if (HOSTFS_I(inode)->fd != -1) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 245 | close_file(&HOSTFS_I(inode)->fd); |
| 246 | HOSTFS_I(inode)->fd = -1; |
| 247 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 248 | } |
| 249 | |
Nick Piggin | fa0d7e3d | 2011-01-07 17:49:49 +1100 | [diff] [blame] | 250 | static void hostfs_i_callback(struct rcu_head *head) |
| 251 | { |
| 252 | struct inode *inode = container_of(head, struct inode, i_rcu); |
| 253 | INIT_LIST_HEAD(&inode->i_dentry); |
| 254 | kfree(HOSTFS_I(inode)); |
| 255 | } |
| 256 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 257 | static void hostfs_destroy_inode(struct inode *inode) |
| 258 | { |
Nick Piggin | fa0d7e3d | 2011-01-07 17:49:49 +1100 | [diff] [blame] | 259 | call_rcu(&inode->i_rcu, hostfs_i_callback); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 260 | } |
| 261 | |
Miklos Szeredi | dd2cc4d | 2008-02-08 04:21:43 -0800 | [diff] [blame] | 262 | static int hostfs_show_options(struct seq_file *seq, struct vfsmount *vfs) |
| 263 | { |
Al Viro | 601d2c3 | 2010-06-06 17:53:01 -0400 | [diff] [blame] | 264 | const char *root_path = vfs->mnt_sb->s_fs_info; |
Miklos Szeredi | dd2cc4d | 2008-02-08 04:21:43 -0800 | [diff] [blame] | 265 | size_t offset = strlen(root_ino) + 1; |
| 266 | |
| 267 | if (strlen(root_path) > offset) |
| 268 | seq_printf(seq, ",%s", root_path + offset); |
| 269 | |
| 270 | return 0; |
| 271 | } |
| 272 | |
Josef 'Jeff' Sipek | ee9b6d6 | 2007-02-12 00:55:41 -0800 | [diff] [blame] | 273 | static const struct super_operations hostfs_sbops = { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 274 | .alloc_inode = hostfs_alloc_inode, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 275 | .destroy_inode = hostfs_destroy_inode, |
Al Viro | e971a6d | 2010-06-06 15:16:17 -0400 | [diff] [blame] | 276 | .evict_inode = hostfs_evict_inode, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 277 | .statfs = hostfs_statfs, |
Miklos Szeredi | dd2cc4d | 2008-02-08 04:21:43 -0800 | [diff] [blame] | 278 | .show_options = hostfs_show_options, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 279 | }; |
| 280 | |
| 281 | int hostfs_readdir(struct file *file, void *ent, filldir_t filldir) |
| 282 | { |
| 283 | void *dir; |
| 284 | char *name; |
| 285 | unsigned long long next, ino; |
| 286 | int error, len; |
| 287 | |
Al Viro | c532222 | 2010-06-06 20:42:10 -0400 | [diff] [blame] | 288 | name = dentry_name(file->f_path.dentry); |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 289 | if (name == NULL) |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 290 | return -ENOMEM; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 291 | dir = open_dir(name, &error); |
Al Viro | e919305 | 2010-06-06 23:16:34 -0400 | [diff] [blame] | 292 | __putname(name); |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 293 | if (dir == NULL) |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 294 | return -error; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 295 | next = file->f_pos; |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 296 | while ((name = read_dir(dir, &next, &ino, &len)) != NULL) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 297 | error = (*filldir)(ent, name, len, file->f_pos, |
| 298 | ino, DT_UNKNOWN); |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 299 | if (error) break; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 300 | file->f_pos = next; |
| 301 | } |
| 302 | close_dir(dir); |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 303 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 304 | } |
| 305 | |
| 306 | int hostfs_file_open(struct inode *ino, struct file *file) |
| 307 | { |
Al Viro | f8ad850 | 2010-06-06 23:49:18 -0400 | [diff] [blame] | 308 | static DEFINE_MUTEX(open_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 309 | char *name; |
Al Viro | aeb5d72 | 2008-09-02 15:28:45 -0400 | [diff] [blame] | 310 | fmode_t mode = 0; |
Al Viro | f8ad850 | 2010-06-06 23:49:18 -0400 | [diff] [blame] | 311 | int err; |
Al Viro | aeb5d72 | 2008-09-02 15:28:45 -0400 | [diff] [blame] | 312 | int r = 0, w = 0, fd; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 313 | |
| 314 | mode = file->f_mode & (FMODE_READ | FMODE_WRITE); |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 315 | if ((mode & HOSTFS_I(ino)->mode) == mode) |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 316 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 317 | |
Al Viro | f8ad850 | 2010-06-06 23:49:18 -0400 | [diff] [blame] | 318 | mode |= HOSTFS_I(ino)->mode; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 319 | |
Al Viro | f8ad850 | 2010-06-06 23:49:18 -0400 | [diff] [blame] | 320 | retry: |
| 321 | if (mode & FMODE_READ) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 322 | r = 1; |
Al Viro | f8ad850 | 2010-06-06 23:49:18 -0400 | [diff] [blame] | 323 | if (mode & FMODE_WRITE) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 324 | w = 1; |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 325 | if (w) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 326 | r = 1; |
| 327 | |
Al Viro | c532222 | 2010-06-06 20:42:10 -0400 | [diff] [blame] | 328 | name = dentry_name(file->f_path.dentry); |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 329 | if (name == NULL) |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 330 | return -ENOMEM; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 331 | |
| 332 | fd = open_file(name, r, w, append); |
Al Viro | e919305 | 2010-06-06 23:16:34 -0400 | [diff] [blame] | 333 | __putname(name); |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 334 | if (fd < 0) |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 335 | return fd; |
Al Viro | f8ad850 | 2010-06-06 23:49:18 -0400 | [diff] [blame] | 336 | |
| 337 | mutex_lock(&open_mutex); |
| 338 | /* somebody else had handled it first? */ |
| 339 | if ((mode & HOSTFS_I(ino)->mode) == mode) { |
| 340 | mutex_unlock(&open_mutex); |
| 341 | return 0; |
| 342 | } |
| 343 | if ((mode | HOSTFS_I(ino)->mode) != mode) { |
| 344 | mode |= HOSTFS_I(ino)->mode; |
| 345 | mutex_unlock(&open_mutex); |
| 346 | close_file(&fd); |
| 347 | goto retry; |
| 348 | } |
| 349 | if (HOSTFS_I(ino)->fd == -1) { |
| 350 | HOSTFS_I(ino)->fd = fd; |
| 351 | } else { |
| 352 | err = replace_file(fd, HOSTFS_I(ino)->fd); |
| 353 | close_file(&fd); |
| 354 | if (err < 0) { |
| 355 | mutex_unlock(&open_mutex); |
| 356 | return err; |
| 357 | } |
| 358 | } |
| 359 | HOSTFS_I(ino)->mode = mode; |
| 360 | mutex_unlock(&open_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 361 | |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 362 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 363 | } |
| 364 | |
Christoph Hellwig | 7ea8085 | 2010-05-26 17:53:25 +0200 | [diff] [blame] | 365 | int hostfs_fsync(struct file *file, int datasync) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 366 | { |
Christoph Hellwig | 7ea8085 | 2010-05-26 17:53:25 +0200 | [diff] [blame] | 367 | return fsync_file(HOSTFS_I(file->f_mapping->host)->fd, datasync); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 368 | } |
| 369 | |
Arjan van de Ven | 4b6f5d2 | 2006-03-28 01:56:42 -0800 | [diff] [blame] | 370 | static const struct file_operations hostfs_file_fops = { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 371 | .llseek = generic_file_llseek, |
Badari Pulavarty | 543ade1 | 2006-09-30 23:28:48 -0700 | [diff] [blame] | 372 | .read = do_sync_read, |
Jens Axboe | 5ffc4ef | 2007-06-01 11:49:19 +0200 | [diff] [blame] | 373 | .splice_read = generic_file_splice_read, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 374 | .aio_read = generic_file_aio_read, |
| 375 | .aio_write = generic_file_aio_write, |
Badari Pulavarty | 543ade1 | 2006-09-30 23:28:48 -0700 | [diff] [blame] | 376 | .write = do_sync_write, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 377 | .mmap = generic_file_mmap, |
| 378 | .open = hostfs_file_open, |
| 379 | .release = NULL, |
| 380 | .fsync = hostfs_fsync, |
| 381 | }; |
| 382 | |
Arjan van de Ven | 4b6f5d2 | 2006-03-28 01:56:42 -0800 | [diff] [blame] | 383 | static const struct file_operations hostfs_dir_fops = { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 384 | .llseek = generic_file_llseek, |
| 385 | .readdir = hostfs_readdir, |
| 386 | .read = generic_read_dir, |
| 387 | }; |
| 388 | |
| 389 | int hostfs_writepage(struct page *page, struct writeback_control *wbc) |
| 390 | { |
| 391 | struct address_space *mapping = page->mapping; |
| 392 | struct inode *inode = mapping->host; |
| 393 | char *buffer; |
| 394 | unsigned long long base; |
| 395 | int count = PAGE_CACHE_SIZE; |
| 396 | int end_index = inode->i_size >> PAGE_CACHE_SHIFT; |
| 397 | int err; |
| 398 | |
| 399 | if (page->index >= end_index) |
| 400 | count = inode->i_size & (PAGE_CACHE_SIZE-1); |
| 401 | |
| 402 | buffer = kmap(page); |
| 403 | base = ((unsigned long long) page->index) << PAGE_CACHE_SHIFT; |
| 404 | |
| 405 | err = write_file(HOSTFS_I(inode)->fd, &base, buffer, count); |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 406 | if (err != count) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 407 | ClearPageUptodate(page); |
| 408 | goto out; |
| 409 | } |
| 410 | |
| 411 | if (base > inode->i_size) |
| 412 | inode->i_size = base; |
| 413 | |
| 414 | if (PageError(page)) |
| 415 | ClearPageError(page); |
| 416 | err = 0; |
| 417 | |
| 418 | out: |
| 419 | kunmap(page); |
| 420 | |
| 421 | unlock_page(page); |
| 422 | return err; |
| 423 | } |
| 424 | |
| 425 | int hostfs_readpage(struct file *file, struct page *page) |
| 426 | { |
| 427 | char *buffer; |
| 428 | long long start; |
| 429 | int err = 0; |
| 430 | |
| 431 | start = (long long) page->index << PAGE_CACHE_SHIFT; |
| 432 | buffer = kmap(page); |
| 433 | err = read_file(FILE_HOSTFS_I(file)->fd, &start, buffer, |
| 434 | PAGE_CACHE_SIZE); |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 435 | if (err < 0) |
| 436 | goto out; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 437 | |
| 438 | memset(&buffer[err], 0, PAGE_CACHE_SIZE - err); |
| 439 | |
| 440 | flush_dcache_page(page); |
| 441 | SetPageUptodate(page); |
| 442 | if (PageError(page)) ClearPageError(page); |
| 443 | err = 0; |
| 444 | out: |
| 445 | kunmap(page); |
| 446 | unlock_page(page); |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 447 | return err; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 448 | } |
| 449 | |
Nick Piggin | ae361ff | 2007-10-16 01:25:17 -0700 | [diff] [blame] | 450 | int hostfs_write_begin(struct file *file, struct address_space *mapping, |
| 451 | loff_t pos, unsigned len, unsigned flags, |
| 452 | struct page **pagep, void **fsdata) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 453 | { |
Nick Piggin | ae361ff | 2007-10-16 01:25:17 -0700 | [diff] [blame] | 454 | pgoff_t index = pos >> PAGE_CACHE_SHIFT; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 455 | |
Nick Piggin | 54566b2 | 2009-01-04 12:00:53 -0800 | [diff] [blame] | 456 | *pagep = grab_cache_page_write_begin(mapping, index, flags); |
Nick Piggin | ae361ff | 2007-10-16 01:25:17 -0700 | [diff] [blame] | 457 | if (!*pagep) |
| 458 | return -ENOMEM; |
| 459 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 460 | } |
| 461 | |
Nick Piggin | ae361ff | 2007-10-16 01:25:17 -0700 | [diff] [blame] | 462 | int hostfs_write_end(struct file *file, struct address_space *mapping, |
| 463 | loff_t pos, unsigned len, unsigned copied, |
| 464 | struct page *page, void *fsdata) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 465 | { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 466 | struct inode *inode = mapping->host; |
Nick Piggin | ae361ff | 2007-10-16 01:25:17 -0700 | [diff] [blame] | 467 | void *buffer; |
| 468 | unsigned from = pos & (PAGE_CACHE_SIZE - 1); |
| 469 | int err; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 470 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 471 | buffer = kmap(page); |
Nick Piggin | ae361ff | 2007-10-16 01:25:17 -0700 | [diff] [blame] | 472 | err = write_file(FILE_HOSTFS_I(file)->fd, &pos, buffer + from, copied); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 473 | kunmap(page); |
Nick Piggin | ae361ff | 2007-10-16 01:25:17 -0700 | [diff] [blame] | 474 | |
| 475 | if (!PageUptodate(page) && err == PAGE_CACHE_SIZE) |
| 476 | SetPageUptodate(page); |
| 477 | |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 478 | /* |
| 479 | * If err > 0, write_file has added err to pos, so we are comparing |
Nick Piggin | ae361ff | 2007-10-16 01:25:17 -0700 | [diff] [blame] | 480 | * i_size against the last byte written. |
| 481 | */ |
| 482 | if (err > 0 && (pos > inode->i_size)) |
| 483 | inode->i_size = pos; |
| 484 | unlock_page(page); |
| 485 | page_cache_release(page); |
| 486 | |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 487 | return err; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 488 | } |
| 489 | |
Christoph Hellwig | f5e54d6 | 2006-06-28 04:26:44 -0700 | [diff] [blame] | 490 | static const struct address_space_operations hostfs_aops = { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 491 | .writepage = hostfs_writepage, |
| 492 | .readpage = hostfs_readpage, |
Paolo 'Blaisorblade' Giarrusso | ffa0aea | 2005-05-01 08:58:56 -0700 | [diff] [blame] | 493 | .set_page_dirty = __set_page_dirty_nobuffers, |
Nick Piggin | ae361ff | 2007-10-16 01:25:17 -0700 | [diff] [blame] | 494 | .write_begin = hostfs_write_begin, |
| 495 | .write_end = hostfs_write_end, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 496 | }; |
| 497 | |
Al Viro | 4754b82 | 2010-06-06 20:33:12 -0400 | [diff] [blame] | 498 | static int read_name(struct inode *ino, char *name) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 499 | { |
Al Viro | 4754b82 | 2010-06-06 20:33:12 -0400 | [diff] [blame] | 500 | dev_t rdev; |
| 501 | struct hostfs_stat st; |
| 502 | int err = stat_file(name, &st, -1); |
| 503 | if (err) |
| 504 | return err; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 505 | |
Al Viro | 5e2df28 | 2010-06-06 19:38:18 -0400 | [diff] [blame] | 506 | /* Reencode maj and min with the kernel encoding.*/ |
Al Viro | 4754b82 | 2010-06-06 20:33:12 -0400 | [diff] [blame] | 507 | rdev = MKDEV(st.maj, st.min); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 508 | |
Al Viro | 4754b82 | 2010-06-06 20:33:12 -0400 | [diff] [blame] | 509 | switch (st.mode & S_IFMT) { |
| 510 | case S_IFLNK: |
Al Viro | d0352d3 | 2010-06-06 21:51:16 -0400 | [diff] [blame] | 511 | ino->i_op = &hostfs_link_iops; |
Al Viro | 4754b82 | 2010-06-06 20:33:12 -0400 | [diff] [blame] | 512 | break; |
| 513 | case S_IFDIR: |
| 514 | ino->i_op = &hostfs_dir_iops; |
| 515 | ino->i_fop = &hostfs_dir_fops; |
| 516 | break; |
| 517 | case S_IFCHR: |
| 518 | case S_IFBLK: |
| 519 | case S_IFIFO: |
| 520 | case S_IFSOCK: |
| 521 | init_special_inode(ino, st.mode & S_IFMT, rdev); |
| 522 | ino->i_op = &hostfs_iops; |
| 523 | break; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 524 | |
Al Viro | 4754b82 | 2010-06-06 20:33:12 -0400 | [diff] [blame] | 525 | default: |
| 526 | ino->i_op = &hostfs_iops; |
| 527 | ino->i_fop = &hostfs_file_fops; |
| 528 | ino->i_mapping->a_ops = &hostfs_aops; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 529 | } |
Al Viro | 4754b82 | 2010-06-06 20:33:12 -0400 | [diff] [blame] | 530 | |
| 531 | ino->i_ino = st.ino; |
| 532 | ino->i_mode = st.mode; |
| 533 | ino->i_nlink = st.nlink; |
| 534 | ino->i_uid = st.uid; |
| 535 | ino->i_gid = st.gid; |
| 536 | ino->i_atime = st.atime; |
| 537 | ino->i_mtime = st.mtime; |
| 538 | ino->i_ctime = st.ctime; |
| 539 | ino->i_size = st.size; |
| 540 | ino->i_blocks = st.blocks; |
| 541 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 542 | } |
| 543 | |
| 544 | int hostfs_create(struct inode *dir, struct dentry *dentry, int mode, |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 545 | struct nameidata *nd) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 546 | { |
| 547 | struct inode *inode; |
| 548 | char *name; |
| 549 | int error, fd; |
| 550 | |
David Howells | 0a370e5 | 2008-02-07 00:15:50 -0800 | [diff] [blame] | 551 | inode = hostfs_iget(dir->i_sb); |
| 552 | if (IS_ERR(inode)) { |
| 553 | error = PTR_ERR(inode); |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 554 | goto out; |
David Howells | 0a370e5 | 2008-02-07 00:15:50 -0800 | [diff] [blame] | 555 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 556 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 557 | error = -ENOMEM; |
Al Viro | c532222 | 2010-06-06 20:42:10 -0400 | [diff] [blame] | 558 | name = dentry_name(dentry); |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 559 | if (name == NULL) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 560 | goto out_put; |
| 561 | |
| 562 | fd = file_create(name, |
| 563 | mode & S_IRUSR, mode & S_IWUSR, mode & S_IXUSR, |
| 564 | mode & S_IRGRP, mode & S_IWGRP, mode & S_IXGRP, |
| 565 | mode & S_IROTH, mode & S_IWOTH, mode & S_IXOTH); |
Al Viro | 4754b82 | 2010-06-06 20:33:12 -0400 | [diff] [blame] | 566 | if (fd < 0) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 567 | error = fd; |
Al Viro | 4754b82 | 2010-06-06 20:33:12 -0400 | [diff] [blame] | 568 | else |
Al Viro | 5e2df28 | 2010-06-06 19:38:18 -0400 | [diff] [blame] | 569 | error = read_name(inode, name); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 570 | |
Al Viro | e919305 | 2010-06-06 23:16:34 -0400 | [diff] [blame] | 571 | __putname(name); |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 572 | if (error) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 573 | goto out_put; |
| 574 | |
| 575 | HOSTFS_I(inode)->fd = fd; |
| 576 | HOSTFS_I(inode)->mode = FMODE_READ | FMODE_WRITE; |
| 577 | d_instantiate(dentry, inode); |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 578 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 579 | |
| 580 | out_put: |
| 581 | iput(inode); |
| 582 | out: |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 583 | return error; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 584 | } |
| 585 | |
| 586 | struct dentry *hostfs_lookup(struct inode *ino, struct dentry *dentry, |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 587 | struct nameidata *nd) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 588 | { |
| 589 | struct inode *inode; |
| 590 | char *name; |
| 591 | int err; |
| 592 | |
David Howells | 0a370e5 | 2008-02-07 00:15:50 -0800 | [diff] [blame] | 593 | inode = hostfs_iget(ino->i_sb); |
| 594 | if (IS_ERR(inode)) { |
| 595 | err = PTR_ERR(inode); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 596 | goto out; |
David Howells | 0a370e5 | 2008-02-07 00:15:50 -0800 | [diff] [blame] | 597 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 598 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 599 | err = -ENOMEM; |
Al Viro | c532222 | 2010-06-06 20:42:10 -0400 | [diff] [blame] | 600 | name = dentry_name(dentry); |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 601 | if (name == NULL) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 602 | goto out_put; |
| 603 | |
| 604 | err = read_name(inode, name); |
Al Viro | 5e2df28 | 2010-06-06 19:38:18 -0400 | [diff] [blame] | 605 | |
Al Viro | e919305 | 2010-06-06 23:16:34 -0400 | [diff] [blame] | 606 | __putname(name); |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 607 | if (err == -ENOENT) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 608 | iput(inode); |
| 609 | inode = NULL; |
| 610 | } |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 611 | else if (err) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 612 | goto out_put; |
| 613 | |
| 614 | d_add(dentry, inode); |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 615 | return NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 616 | |
| 617 | out_put: |
| 618 | iput(inode); |
| 619 | out: |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 620 | return ERR_PTR(err); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 621 | } |
| 622 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 623 | int hostfs_link(struct dentry *to, struct inode *ino, struct dentry *from) |
| 624 | { |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 625 | char *from_name, *to_name; |
| 626 | int err; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 627 | |
Al Viro | c532222 | 2010-06-06 20:42:10 -0400 | [diff] [blame] | 628 | if ((from_name = dentry_name(from)) == NULL) |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 629 | return -ENOMEM; |
Al Viro | c532222 | 2010-06-06 20:42:10 -0400 | [diff] [blame] | 630 | to_name = dentry_name(to); |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 631 | if (to_name == NULL) { |
Al Viro | e919305 | 2010-06-06 23:16:34 -0400 | [diff] [blame] | 632 | __putname(from_name); |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 633 | return -ENOMEM; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 634 | } |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 635 | err = link_file(to_name, from_name); |
Al Viro | e919305 | 2010-06-06 23:16:34 -0400 | [diff] [blame] | 636 | __putname(from_name); |
| 637 | __putname(to_name); |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 638 | return err; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 639 | } |
| 640 | |
| 641 | int hostfs_unlink(struct inode *ino, struct dentry *dentry) |
| 642 | { |
| 643 | char *file; |
| 644 | int err; |
| 645 | |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 646 | if (append) |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 647 | return -EPERM; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 648 | |
Al Viro | f8d7e18 | 2010-06-06 23:19:04 -0400 | [diff] [blame] | 649 | if ((file = dentry_name(dentry)) == NULL) |
| 650 | return -ENOMEM; |
| 651 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 652 | err = unlink_file(file); |
Al Viro | e919305 | 2010-06-06 23:16:34 -0400 | [diff] [blame] | 653 | __putname(file); |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 654 | return err; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 655 | } |
| 656 | |
| 657 | int hostfs_symlink(struct inode *ino, struct dentry *dentry, const char *to) |
| 658 | { |
| 659 | char *file; |
| 660 | int err; |
| 661 | |
Al Viro | c532222 | 2010-06-06 20:42:10 -0400 | [diff] [blame] | 662 | if ((file = dentry_name(dentry)) == NULL) |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 663 | return -ENOMEM; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 664 | err = make_symlink(file, to); |
Al Viro | e919305 | 2010-06-06 23:16:34 -0400 | [diff] [blame] | 665 | __putname(file); |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 666 | return err; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 667 | } |
| 668 | |
| 669 | int hostfs_mkdir(struct inode *ino, struct dentry *dentry, int mode) |
| 670 | { |
| 671 | char *file; |
| 672 | int err; |
| 673 | |
Al Viro | c532222 | 2010-06-06 20:42:10 -0400 | [diff] [blame] | 674 | if ((file = dentry_name(dentry)) == NULL) |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 675 | return -ENOMEM; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 676 | err = do_mkdir(file, mode); |
Al Viro | e919305 | 2010-06-06 23:16:34 -0400 | [diff] [blame] | 677 | __putname(file); |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 678 | return err; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 679 | } |
| 680 | |
| 681 | int hostfs_rmdir(struct inode *ino, struct dentry *dentry) |
| 682 | { |
| 683 | char *file; |
| 684 | int err; |
| 685 | |
Al Viro | c532222 | 2010-06-06 20:42:10 -0400 | [diff] [blame] | 686 | if ((file = dentry_name(dentry)) == NULL) |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 687 | return -ENOMEM; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 688 | err = do_rmdir(file); |
Al Viro | e919305 | 2010-06-06 23:16:34 -0400 | [diff] [blame] | 689 | __putname(file); |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 690 | return err; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 691 | } |
| 692 | |
| 693 | int hostfs_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev) |
| 694 | { |
| 695 | struct inode *inode; |
| 696 | char *name; |
David Howells | 0a370e5 | 2008-02-07 00:15:50 -0800 | [diff] [blame] | 697 | int err; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 698 | |
David Howells | 0a370e5 | 2008-02-07 00:15:50 -0800 | [diff] [blame] | 699 | inode = hostfs_iget(dir->i_sb); |
| 700 | if (IS_ERR(inode)) { |
| 701 | err = PTR_ERR(inode); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 702 | goto out; |
David Howells | 0a370e5 | 2008-02-07 00:15:50 -0800 | [diff] [blame] | 703 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 704 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 705 | err = -ENOMEM; |
Al Viro | c532222 | 2010-06-06 20:42:10 -0400 | [diff] [blame] | 706 | name = dentry_name(dentry); |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 707 | if (name == NULL) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 708 | goto out_put; |
| 709 | |
| 710 | init_special_inode(inode, mode, dev); |
Johannes Stezenbach | 88f6cd0 | 2007-01-29 13:19:44 -0800 | [diff] [blame] | 711 | err = do_mknod(name, mode, MAJOR(dev), MINOR(dev)); |
Al Viro | e919305 | 2010-06-06 23:16:34 -0400 | [diff] [blame] | 712 | if (!err) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 713 | goto out_free; |
| 714 | |
| 715 | err = read_name(inode, name); |
Al Viro | e919305 | 2010-06-06 23:16:34 -0400 | [diff] [blame] | 716 | __putname(name); |
Al Viro | 5e2df28 | 2010-06-06 19:38:18 -0400 | [diff] [blame] | 717 | if (err) |
| 718 | goto out_put; |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 719 | if (err) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 720 | goto out_put; |
| 721 | |
| 722 | d_instantiate(dentry, inode); |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 723 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 724 | |
| 725 | out_free: |
Al Viro | e919305 | 2010-06-06 23:16:34 -0400 | [diff] [blame] | 726 | __putname(name); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 727 | out_put: |
| 728 | iput(inode); |
| 729 | out: |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 730 | return err; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 731 | } |
| 732 | |
| 733 | int hostfs_rename(struct inode *from_ino, struct dentry *from, |
| 734 | struct inode *to_ino, struct dentry *to) |
| 735 | { |
| 736 | char *from_name, *to_name; |
| 737 | int err; |
| 738 | |
Al Viro | c532222 | 2010-06-06 20:42:10 -0400 | [diff] [blame] | 739 | if ((from_name = dentry_name(from)) == NULL) |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 740 | return -ENOMEM; |
Al Viro | c532222 | 2010-06-06 20:42:10 -0400 | [diff] [blame] | 741 | if ((to_name = dentry_name(to)) == NULL) { |
Al Viro | e919305 | 2010-06-06 23:16:34 -0400 | [diff] [blame] | 742 | __putname(from_name); |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 743 | return -ENOMEM; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 744 | } |
| 745 | err = rename_file(from_name, to_name); |
Al Viro | e919305 | 2010-06-06 23:16:34 -0400 | [diff] [blame] | 746 | __putname(from_name); |
| 747 | __putname(to_name); |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 748 | return err; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 749 | } |
| 750 | |
Nick Piggin | b74c79e | 2011-01-07 17:49:58 +1100 | [diff] [blame] | 751 | int hostfs_permission(struct inode *ino, int desired, unsigned int flags) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 752 | { |
| 753 | char *name; |
| 754 | int r = 0, w = 0, x = 0, err; |
| 755 | |
Nick Piggin | b74c79e | 2011-01-07 17:49:58 +1100 | [diff] [blame] | 756 | if (flags & IPERM_FLAG_RCU) |
| 757 | return -ECHILD; |
| 758 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 759 | if (desired & MAY_READ) r = 1; |
| 760 | if (desired & MAY_WRITE) w = 1; |
| 761 | if (desired & MAY_EXEC) x = 1; |
Al Viro | c532222 | 2010-06-06 20:42:10 -0400 | [diff] [blame] | 762 | name = inode_name(ino); |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 763 | if (name == NULL) |
| 764 | return -ENOMEM; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 765 | |
| 766 | if (S_ISCHR(ino->i_mode) || S_ISBLK(ino->i_mode) || |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 767 | S_ISFIFO(ino->i_mode) || S_ISSOCK(ino->i_mode)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 768 | err = 0; |
| 769 | else |
| 770 | err = access_file(name, r, w, x); |
Al Viro | e919305 | 2010-06-06 23:16:34 -0400 | [diff] [blame] | 771 | __putname(name); |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 772 | if (!err) |
Nick Piggin | b74c79e | 2011-01-07 17:49:58 +1100 | [diff] [blame] | 773 | err = generic_permission(ino, desired, flags, NULL); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 774 | return err; |
| 775 | } |
| 776 | |
| 777 | int hostfs_setattr(struct dentry *dentry, struct iattr *attr) |
| 778 | { |
Christoph Hellwig | 1025774 | 2010-06-04 11:30:02 +0200 | [diff] [blame] | 779 | struct inode *inode = dentry->d_inode; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 780 | struct hostfs_iattr attrs; |
| 781 | char *name; |
| 782 | int err; |
| 783 | |
Christoph Hellwig | 1025774 | 2010-06-04 11:30:02 +0200 | [diff] [blame] | 784 | int fd = HOSTFS_I(inode)->fd; |
Alberto Bertogli | 5822b7f | 2007-05-08 00:23:16 -0700 | [diff] [blame] | 785 | |
Christoph Hellwig | 1025774 | 2010-06-04 11:30:02 +0200 | [diff] [blame] | 786 | err = inode_change_ok(inode, attr); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 787 | if (err) |
| 788 | return err; |
| 789 | |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 790 | if (append) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 791 | attr->ia_valid &= ~ATTR_SIZE; |
| 792 | |
| 793 | attrs.ia_valid = 0; |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 794 | if (attr->ia_valid & ATTR_MODE) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 795 | attrs.ia_valid |= HOSTFS_ATTR_MODE; |
| 796 | attrs.ia_mode = attr->ia_mode; |
| 797 | } |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 798 | if (attr->ia_valid & ATTR_UID) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 799 | attrs.ia_valid |= HOSTFS_ATTR_UID; |
| 800 | attrs.ia_uid = attr->ia_uid; |
| 801 | } |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 802 | if (attr->ia_valid & ATTR_GID) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 803 | attrs.ia_valid |= HOSTFS_ATTR_GID; |
| 804 | attrs.ia_gid = attr->ia_gid; |
| 805 | } |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 806 | if (attr->ia_valid & ATTR_SIZE) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 807 | attrs.ia_valid |= HOSTFS_ATTR_SIZE; |
| 808 | attrs.ia_size = attr->ia_size; |
| 809 | } |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 810 | if (attr->ia_valid & ATTR_ATIME) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 811 | attrs.ia_valid |= HOSTFS_ATTR_ATIME; |
| 812 | attrs.ia_atime = attr->ia_atime; |
| 813 | } |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 814 | if (attr->ia_valid & ATTR_MTIME) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 815 | attrs.ia_valid |= HOSTFS_ATTR_MTIME; |
| 816 | attrs.ia_mtime = attr->ia_mtime; |
| 817 | } |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 818 | if (attr->ia_valid & ATTR_CTIME) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 819 | attrs.ia_valid |= HOSTFS_ATTR_CTIME; |
| 820 | attrs.ia_ctime = attr->ia_ctime; |
| 821 | } |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 822 | if (attr->ia_valid & ATTR_ATIME_SET) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 823 | attrs.ia_valid |= HOSTFS_ATTR_ATIME_SET; |
| 824 | } |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 825 | if (attr->ia_valid & ATTR_MTIME_SET) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 826 | attrs.ia_valid |= HOSTFS_ATTR_MTIME_SET; |
| 827 | } |
Al Viro | c532222 | 2010-06-06 20:42:10 -0400 | [diff] [blame] | 828 | name = dentry_name(dentry); |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 829 | if (name == NULL) |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 830 | return -ENOMEM; |
Alberto Bertogli | 5822b7f | 2007-05-08 00:23:16 -0700 | [diff] [blame] | 831 | err = set_attr(name, &attrs, fd); |
Al Viro | e919305 | 2010-06-06 23:16:34 -0400 | [diff] [blame] | 832 | __putname(name); |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 833 | if (err) |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 834 | return err; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 835 | |
Christoph Hellwig | 1025774 | 2010-06-04 11:30:02 +0200 | [diff] [blame] | 836 | if ((attr->ia_valid & ATTR_SIZE) && |
| 837 | attr->ia_size != i_size_read(inode)) { |
| 838 | int error; |
| 839 | |
| 840 | error = vmtruncate(inode, attr->ia_size); |
| 841 | if (err) |
| 842 | return err; |
| 843 | } |
| 844 | |
| 845 | setattr_copy(inode, attr); |
| 846 | mark_inode_dirty(inode); |
| 847 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 848 | } |
| 849 | |
Arjan van de Ven | 92e1d5b | 2007-02-12 00:55:39 -0800 | [diff] [blame] | 850 | static const struct inode_operations hostfs_iops = { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 851 | .create = hostfs_create, |
| 852 | .link = hostfs_link, |
| 853 | .unlink = hostfs_unlink, |
| 854 | .symlink = hostfs_symlink, |
| 855 | .mkdir = hostfs_mkdir, |
| 856 | .rmdir = hostfs_rmdir, |
| 857 | .mknod = hostfs_mknod, |
| 858 | .rename = hostfs_rename, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 859 | .permission = hostfs_permission, |
| 860 | .setattr = hostfs_setattr, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 861 | }; |
| 862 | |
Arjan van de Ven | 92e1d5b | 2007-02-12 00:55:39 -0800 | [diff] [blame] | 863 | static const struct inode_operations hostfs_dir_iops = { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 864 | .create = hostfs_create, |
| 865 | .lookup = hostfs_lookup, |
| 866 | .link = hostfs_link, |
| 867 | .unlink = hostfs_unlink, |
| 868 | .symlink = hostfs_symlink, |
| 869 | .mkdir = hostfs_mkdir, |
| 870 | .rmdir = hostfs_rmdir, |
| 871 | .mknod = hostfs_mknod, |
| 872 | .rename = hostfs_rename, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 873 | .permission = hostfs_permission, |
| 874 | .setattr = hostfs_setattr, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 875 | }; |
| 876 | |
Al Viro | d0352d3 | 2010-06-06 21:51:16 -0400 | [diff] [blame] | 877 | static void *hostfs_follow_link(struct dentry *dentry, struct nameidata *nd) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 878 | { |
Al Viro | d0352d3 | 2010-06-06 21:51:16 -0400 | [diff] [blame] | 879 | char *link = __getname(); |
| 880 | if (link) { |
| 881 | char *path = dentry_name(dentry); |
| 882 | int err = -ENOMEM; |
| 883 | if (path) { |
Al Viro | 3b6036d | 2010-08-18 06:21:10 -0400 | [diff] [blame] | 884 | err = hostfs_do_readlink(path, link, PATH_MAX); |
Al Viro | d0352d3 | 2010-06-06 21:51:16 -0400 | [diff] [blame] | 885 | if (err == PATH_MAX) |
| 886 | err = -E2BIG; |
Al Viro | e919305 | 2010-06-06 23:16:34 -0400 | [diff] [blame] | 887 | __putname(path); |
Al Viro | d0352d3 | 2010-06-06 21:51:16 -0400 | [diff] [blame] | 888 | } |
| 889 | if (err < 0) { |
| 890 | __putname(link); |
| 891 | link = ERR_PTR(err); |
| 892 | } |
| 893 | } else { |
| 894 | link = ERR_PTR(-ENOMEM); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 895 | } |
Al Viro | d0352d3 | 2010-06-06 21:51:16 -0400 | [diff] [blame] | 896 | |
| 897 | nd_set_link(nd, link); |
| 898 | return NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 899 | } |
| 900 | |
Al Viro | d0352d3 | 2010-06-06 21:51:16 -0400 | [diff] [blame] | 901 | static void hostfs_put_link(struct dentry *dentry, struct nameidata *nd, void *cookie) |
| 902 | { |
| 903 | char *s = nd_get_link(nd); |
| 904 | if (!IS_ERR(s)) |
| 905 | __putname(s); |
| 906 | } |
| 907 | |
| 908 | static const struct inode_operations hostfs_link_iops = { |
| 909 | .readlink = generic_readlink, |
| 910 | .follow_link = hostfs_follow_link, |
| 911 | .put_link = hostfs_put_link, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 912 | }; |
| 913 | |
| 914 | static int hostfs_fill_sb_common(struct super_block *sb, void *d, int silent) |
| 915 | { |
| 916 | struct inode *root_inode; |
Paolo 'Blaisorblade' Giarrusso | 75e8def | 2007-03-29 01:20:33 -0700 | [diff] [blame] | 917 | char *host_root_path, *req_root = d; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 918 | int err; |
| 919 | |
| 920 | sb->s_blocksize = 1024; |
| 921 | sb->s_blocksize_bits = 10; |
| 922 | sb->s_magic = HOSTFS_SUPER_MAGIC; |
| 923 | sb->s_op = &hostfs_sbops; |
Al Viro | f772c4a | 2011-01-12 16:47:00 -0500 | [diff] [blame] | 924 | sb->s_d_op = &hostfs_dentry_ops; |
Wolfgang Illmeyer | 752fa51 | 2009-06-30 11:41:44 -0700 | [diff] [blame] | 925 | sb->s_maxbytes = MAX_LFS_FILESIZE; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 926 | |
Paolo 'Blaisorblade' Giarrusso | a6eb0be | 2007-03-07 20:41:08 -0800 | [diff] [blame] | 927 | /* NULL is printed as <NULL> by sprintf: avoid that. */ |
Paolo 'Blaisorblade' Giarrusso | 75e8def | 2007-03-29 01:20:33 -0700 | [diff] [blame] | 928 | if (req_root == NULL) |
| 929 | req_root = ""; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 930 | |
| 931 | err = -ENOMEM; |
Al Viro | 601d2c3 | 2010-06-06 17:53:01 -0400 | [diff] [blame] | 932 | sb->s_fs_info = host_root_path = |
| 933 | kmalloc(strlen(root_ino) + strlen(req_root) + 2, GFP_KERNEL); |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 934 | if (host_root_path == NULL) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 935 | goto out; |
| 936 | |
Paolo 'Blaisorblade' Giarrusso | 75e8def | 2007-03-29 01:20:33 -0700 | [diff] [blame] | 937 | sprintf(host_root_path, "%s/%s", root_ino, req_root); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 938 | |
Al Viro | 52b209f | 2010-06-06 18:43:19 -0400 | [diff] [blame] | 939 | root_inode = new_inode(sb); |
| 940 | if (!root_inode) |
Al Viro | 601d2c3 | 2010-06-06 17:53:01 -0400 | [diff] [blame] | 941 | goto out; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 942 | |
Al Viro | 4754b82 | 2010-06-06 20:33:12 -0400 | [diff] [blame] | 943 | err = read_name(root_inode, host_root_path); |
| 944 | if (err) |
| 945 | goto out_put; |
Al Viro | 52b209f | 2010-06-06 18:43:19 -0400 | [diff] [blame] | 946 | |
Al Viro | 4754b82 | 2010-06-06 20:33:12 -0400 | [diff] [blame] | 947 | if (S_ISLNK(root_inode->i_mode)) { |
Al Viro | 52b209f | 2010-06-06 18:43:19 -0400 | [diff] [blame] | 948 | char *name = follow_link(host_root_path); |
| 949 | if (IS_ERR(name)) |
| 950 | err = PTR_ERR(name); |
| 951 | else |
| 952 | err = read_name(root_inode, name); |
| 953 | kfree(name); |
Al Viro | 4754b82 | 2010-06-06 20:33:12 -0400 | [diff] [blame] | 954 | if (err) |
| 955 | goto out_put; |
Al Viro | 52b209f | 2010-06-06 18:43:19 -0400 | [diff] [blame] | 956 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 957 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 958 | err = -ENOMEM; |
| 959 | sb->s_root = d_alloc_root(root_inode); |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 960 | if (sb->s_root == NULL) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 961 | goto out_put; |
| 962 | |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 963 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 964 | |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 965 | out_put: |
| 966 | iput(root_inode); |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 967 | out: |
| 968 | return err; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 969 | } |
| 970 | |
Al Viro | 3c26ff6 | 2010-07-25 11:46:36 +0400 | [diff] [blame] | 971 | static struct dentry *hostfs_read_sb(struct file_system_type *type, |
David Howells | 454e239 | 2006-06-23 02:02:57 -0700 | [diff] [blame] | 972 | int flags, const char *dev_name, |
Al Viro | 3c26ff6 | 2010-07-25 11:46:36 +0400 | [diff] [blame] | 973 | void *data) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 974 | { |
Al Viro | 3c26ff6 | 2010-07-25 11:46:36 +0400 | [diff] [blame] | 975 | return mount_nodev(type, flags, data, hostfs_fill_sb_common); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 976 | } |
| 977 | |
Al Viro | 601d2c3 | 2010-06-06 17:53:01 -0400 | [diff] [blame] | 978 | static void hostfs_kill_sb(struct super_block *s) |
| 979 | { |
| 980 | kill_anon_super(s); |
| 981 | kfree(s->s_fs_info); |
| 982 | } |
| 983 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 984 | static struct file_system_type hostfs_type = { |
| 985 | .owner = THIS_MODULE, |
| 986 | .name = "hostfs", |
Al Viro | 3c26ff6 | 2010-07-25 11:46:36 +0400 | [diff] [blame] | 987 | .mount = hostfs_read_sb, |
Al Viro | 601d2c3 | 2010-06-06 17:53:01 -0400 | [diff] [blame] | 988 | .kill_sb = hostfs_kill_sb, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 989 | .fs_flags = 0, |
| 990 | }; |
| 991 | |
| 992 | static int __init init_hostfs(void) |
| 993 | { |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 994 | return register_filesystem(&hostfs_type); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 995 | } |
| 996 | |
| 997 | static void __exit exit_hostfs(void) |
| 998 | { |
| 999 | unregister_filesystem(&hostfs_type); |
| 1000 | } |
| 1001 | |
| 1002 | module_init(init_hostfs) |
| 1003 | module_exit(exit_hostfs) |
| 1004 | MODULE_LICENSE("GPL"); |